Must we continue to teach students to make cloth? - Journal of

Tired teachers keep students occupied with busy work and promote poppycock. This author calls for a spring-cleaning of the 'mental closets' of chemist...
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provoccrtive opinion Must We Continue To Teach Students To Make Cloth? Dan M. Sullivan University of Nebraska, Omaha, NE 68182 I n the December 28, 1988 issue of the New York IIFmes, Steven Greenhouse described a call by teachers in France for simplified rules of spelling ( I ) . The teachers reasoned that time spent memorizingcapricious rules wuld he better spent on mathematics or science. I can't argue with this suggestion; in fad, I believe we would he wise to simplify the spelling of words in English.' Not that I don't think spelling is important; I was runner-up in the Adams County, Iowa Spelling Contest in 1950, and I'm still learning. I have to admit, though, that a s a teacher of chemistry, I would like to simplify the process of education, and children could use the extra time to study science. Most educators treat their subjects a s a herd of sicred cows to be defended against anv change. Recently, however, a n event occurred that causedme to wonder whether reexamination of some of these sacred wws might he in order. A student described the following incident: his 12-yearold son loves math but dislikes the repetition of long division and multiplication. He asked to he allowed to demonstrate his skill a t these processes and to then use a calculator so that he wuld speAd more time on story pmhlems and eeometrv. The teacher denied the reauest. warnmg that &e calculator m~ghtbreak and that i h e student would then have to oerform the 1onedivislon"bv hand.Thc child, a n excellent kudent, replie: that his akestors had once learned to make their own cloth. and that the teacher's rcasonlng would a s rcadlly support the assrrtlon that we should ull st111learn to make our own cloth rind clothes in case the machinery should break. This anecdote struck a chord with me. Few of us remember how to fmd the square root of a numher without using a calculator. Few memorize atomic weights or numbers. I seriously doubt that anyone still uses a blowpipe and charcoal block in spite of the fact that this puts real meaning into the word "reduction". Still, some portions of a typical course of instruction in chemistry may correspond to leamingcomplicated spellings of French words, or even to repetitive practice a t lone division. Verv " urobablv. . " . each of us cmphnsizes some topic that our colleaguen consider h u m less at hrst und wasteful of student time at worst. Hut like the French, who consider those who spell words a s they are pronounced to he inferior to those who spell words in the way they aren't pronounced, we may teach some concepts simply because we believe a competent chemist should have learned them. Some of us still require students to learn the names of gas laws a s well a s their manipulations. Some instructors teach the concept of normality; some don't. Most of us no longer use flame tests. But some probably require students to memorize esoteric names and structures or "name" reactions they forget during the hours following the final exam, and most of us have a pet mechanism or hypothesis to bestow on the bewildered. Certainly, we teach techniques of spectroscopy and separations, but many upper-level chemistry students stumble over identification of a n ester or amide bond in a structural formula (particularly if the compound isn't drawn right-side up or acid-end first) or are

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puzzled when asked to deduce from a structural formula whether a particular amino acid would he water-soluble. How often have our students waded through - .vaaees - of proofs and mechanisms to emerge from the final examination and from the course with a n excellent letter made hut little knowledge of the actual applications and characteristics of compouuds involved, and worse, little intention of retaining much of the material that we consider prereqnisite for other courses? To anvone who answers this auestion ''rarely, I suggest a visit to the wmpany that purchases used textbooks a t the end of the semester. We need coordinated curricula in science and nonscience courses. We need to get our facts straight and confront those who u e r ~ e t n a t e~ o ~ v c o cAn k . amazing number of . o.." history and students are still t a u i h t that Columbus proved the world round. and a disturhinglv 1a1.g.e number i f high schoolbiology teachers believe thathumans and dinosaurs roamed the earth together. In chemistly, the equivalent of such statements may he found in our unqnestioniug acceptance of the oftenrunsupported assertions concerning the environment by writers and talk-show . popular . . hosts (2-4). The point of mv ooinionis that tired teachers tend to keen their students "occupied with busywork. Students a i e blocked in their educational develoument bv renetition of unexciting activities and are forced to memorize superfluous information. Rather than using a single unit for conversions between the metric and English systems of weights, we often expect students to memorize multiple conversion relationships such a s the fact that 1lh is equivalent in weight to 453.6 g and 1 kg is equivalent to 2.2 lh. On the elementary school level, students rarely perform science ex eriments which involve measurements and calculations. On the graduate level, we may require competence in a foreign language not for the challenge, beauty, and understanding, hut simply because we ourselves were required to learn a foreign language. Although I helieve students need a n effective understanding of gas laws, stoichiometry, unit conversions, and nomenclature, I think t h a t we sometimes overemphasize these concepts and avoid some useful relationships in chemistrv. Whv not allow each examinee to bring to a n occasional exam a note card or sheet containing anv information d e ~ i r e d ARer ?~ all, we chemists use re?er&ce works, a s do physicians,

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The new Random House Dictionaryof the English Language lists "womyn"as an alternative spelling for 'Woman'' and 'Women". 2Calcuiation~ made in connection withdramaticexperimentsmake science and mathematics meaningful and interesting. By the third or fourth grade, students could measure the dimensions of a can and calculate the surface area. They could boil water in the can, seal it, and then crush the can with atmospheric pressure (*.The formula: Force = (Pressure)(Area)allows calculation of the force on the can. I've tried several variations, from allowing students to bring a single note card to allowing them to bring alltheir notes. Having too many notes simply promotes confusion, but having a single note card helps students to focus on the most important concepts.

pharmacists, and engineers. Is the act of memorizing constants, conversion units, and names really more important than the ability to use these concepts? Once, I taught biochemistry as I was taught, emphasizing rotememorizationof pathways andformulas. I now emphasize control mechanisms and interrelationships of metabolic cycles more than memorization of steps in pathways. I must admit that I have not accepted without question all of the changes in units and nomenclature prop&ed during the last several decades, and I remain skeptical of the putative relations hi^ between scholars hi^ as measured bv research and by teaching. But science remains the systematic approach to the acauisition of knowledee. - , and chemistry remains the central study uniting numerous branches of science . . . in short, the best game in town. Teachers need to be able to expect that students entering their classes will possess fundamental skills in science and in communication. Elementary and high school teachers need to know what we will expect of their graduates. All too often, students are simply drilled in the repetition of the same subiect matter in course after course. All too oPcen. students "of high school chemistry are taught what their teachers learned in freshman-level colleee chemistrv classes (if that happens to be moleculur-orbital theory, the high schooleraduate mav bea whiz at M a .I~uta strikeout at'bescriptive chemistryj. And all too often; we continue to

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teach students the equivalent of making cloth, convincing ourselves that they may one day find themselves in a society with broken cloth-makingmachinery. Instead, chemists could draw upon the experience and services of the Ametican ~ h e m i c a i ~ o c ito e ttake ~ the lead in revolutionizing the educational system. Let's begin by offering to help elementary school teachers devise learning experiences that internate elementary concepts of science and mathematics. wecan do this in by &aking educational devices such as science toys and Wonderscience magazine available for each classroom. Let's make our expectations plain and demand that our first-year college students come to our classes equipped with fundamental skills, and let's expand on those skills with well-designed curricula. It's time to start cleanine the cobwebs out of mental closets and replacing them with-modern tools that can be mastered and then maintained in order to allow time and soace for new concepts. It is time to relegntr the cloth making to the machinery and the long dlvision to the calculators. Literature Cited 1.Greenhouse, S. Nem Yark nmes 1988, (Dec. 281.1. 2. G. N ~ RWS ~ U M ~ iC m ,2 m . 1 ~ 2 1 . 3. Hooper, J. Now York Tim* 1990,(Nov. 25L38. 4.Tieme?, J Ne&,YnrR fimsl89D.1Dec 2). 52. 5 . Alyea, H.N.: Dutton, F. b. Tested fimansfmtians in Chemistry 6th ed.; Journal of Chemical Education: Easton, PA, 1965: p 23.

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